表上的MySQL ALTER TABLE太大而无法复制

When adding a column to a MyISAM table, MySQL will Create>Copy>Drop>Rename. I have a table which is sufficiently large that it cannot be duplicated in the server's remaining free space. Attempting to add a column then results in the disk filling. Time is not an issue here, neither is table availability, just disk space.When adding a column to a MyISAM table, MySQL w